Brush and weed trimming machines, utilizing a cutting element in the form of segments of plastic string trimmer line, are in widespread use. Many of these machines are hand-held machines; and heavier duty machines utilize a motor and rotating string trimmer head mounted on a wheeled carriage. The cutting element in both type of these machines typically is in the form of a length of nylon monofilament line, carried by a rotating head and extending outwardly from the head. Rotating the head at relatively high speeds (4,000 to 10,000 RPM for example), causes the line to strike and sever grass, weeds and brush in the path of the spinning line.
The plastic line which is used in string trimmer machines wears out, breaks, or otherwise becomes depleted during operation of the machine. As a consequence, it is necessary periodically to replenish the line as it is consumed. Many commercial machines, whether they are wheeled machines or hand-held machines, employ cut length segments of line with the line segments entirely replaced once they are worn to a point near the rotating hub on which they are mounted. Many hand-held machines employ a reservoir of coiled line, which is fed out of the reservoir by centrifugal force through what is known as a xe2x80x9cbump and feedxe2x80x9d mechanism. These machines store a relatively long length of line in the reservoir on the rotating head; and line is fed out through an opening in the head, as needed, when it becomes depleted.
Refill line for string trimmer machines typically has been packaged in relatively long lengths in the form of coils, from which desired lengths of line may be drawn for use in either fixed length string trimmer machines or the bump and feed machines described briefly above. One of the oldest packages for holding string trimmer line (which typically has a diameter of 0.065xe2x80x3 to 0.155xe2x80x3) is in the form of a rectangular cardboard box with a hole in one of its faces. The line is wound into a coil and then placed immediately into the box. The box then is closed and sealed to contain the line. The inner end of the line is started through the hole, which typically is of a 2xe2x80x3 diameter or so. The line is removed by pulling it out of the hole.
Another package for string trimmer line has been made in the form of a donut-like shape with an open slot on the outer circumference. In this package, the two halves are sealed together at their centers (the center of the donut) with a donut or tire-like shape about the center. A slot between the two halves is left in the external circumference of the donut. The line then is either wound into the package by rotating the package after the center has been sealed, or by first winding a coil of the line, placing a temporary retainer on the coil, and then placing the coil between the two halves of the donut, which subsequently are sealed together at the center. Line is removed from this package by rotating the line through the outside diameter of the package.
Another type of package has been formed by providing a generally cylindrically shaped open-face container, which is provided with a lid. The line is wound into a coil and then placed in the container, which then is sealed with a lid with a hole through it. This assembly and the removal of line from this package is very much the same as from the cardboard box package described previously.
Another approach which has been used to package string trimmer line is to form loops of line, which are wound and taped. The taped loops are placed into a blister cup, which then is sealed to a backing. Once again, it should be noted that this technique requires the loops of line first to be wound and taped, and then placed into a package which is sealed around the line after it has been configured to fit into the package.
A different technique is disclosed in the U.S. Pat. No. 6,109,005 to Fogle. In the package of this patent, a bubble or blister of thermoplastic material is heat sealed onto a thermoplastic backing which has a hole in it. Line then is spiral wound into the previously sealed package by means of a winding machine to fill the package with line of the desired total length. Once the desired amount of line has been wound into the package, it is severed. The inside end may be withdrawn through the hole to supply desired lengths of line for replacement in conjunction with string trimmer machines. An advantage of the package shown in the Fogle patent is that the spring pressure of the line in the package is not sufficient to break the thermosealed package apart; so that even line of the larger diameters may be wound in a relatively tight circle into a package of this type without concern that the package subsequently may burst.
The U.S. Pat. No. 1,154,212 to Scloss; Percelay U.S. Pat. No. 3,402,810 and de Roure U.S. Pat. No. 4,637,516 are all directed to dispensing containers for different types of materials. In all of these, however, a coil of material first is formed, then placed inside the package, which is sealed around the coil. In the package of Schloss, the container is used for dispensing flat rolls of fabric tape or the like. In the device of Percelay, a coil of twine is formed; and then it is sealed into the package. Finally, in the package of de Roure, the coil of material is a wound coil of wire tie material. In the packages of all of these patents, the coil is placed into a portion of the package, and the package then is sealed around the coil. The material is drawn from a center coil hole in the package; but in none of the packages of these patents is the material wound into the package after the package has been either partially or completely formed.
The patent to Milburn U.S. Pat. No. 4,974,789 is directed to a dispensing package for a fiber optic cable. This package is a relatively complex configuration having two mating members which are attached together by means of a separator. The mating members have centrally located openings and are adjoined at their mating edges to define a cavity between them. The separator divides the cavity into two different parts; and each of these parts or chambers holds a circularly coiled portion of a cable. The cable passes through the separator; so that opposite ends of the cable exit, respectively, from the central apertures of each of the two mating members. Thus, the cable can be pulled out of the package from opposite sides (of course, by pulling on different ends). The fiber optic cable which is provided in the package is for medical purposes; and the package further is designed to allow sterilization of the package and cable, and also is designed to permit the reinsertion of the cable into the package.
The U.S. Pat. No. 4,396,165 to Bates is directed to a method and apparatus for loading a coil of steel strapping material into a dispensing carton. The carton is in the form of a relatively flat rectangular box. One of the flat surfaces or walls of the carton has a central circular aperture in it.
To fill the carton of Bates, the carton is mounted on a mandrel, which passes through the circular aperture in the carton. The mandrel has a slot in its end; and the leading end of a supply of steel strapping is fed through an open end of the carton (the other three ends or edges being closed) and is inserted into the slot in the end of the mandrel. The mandrel is rotated, and a coil of the steel strapping is wound into the box. When the desired length has been wound into the box, the mandrel is withdrawn, leaving the leading end available for access through the hole. The open side of the box then is closed to seal the carton. Lengths of strap then are withdrawn from the center of the rectangular carton as needed.
It is desirable to provide a package and a method for packaging plastic string trimmer line in a pre-formed sealed package, from which the line can be withdrawn either from the external edge of the package, or from a hole located at its center.
It is an object of this invention to provide an improved string trimmer line package and method of packaging.
It is another object of this invention to provide an improved relatively flat package for string trimmer line.
It is an additional object of this invention to provide an improved generally flat package for string trimmer line, from which the line may be withdrawn either from the center or from the periphery of the package.
It is a further object of this invention to provide a method for packaging plastic string trimmer line in a sealed, shallow plastic package, with the line being wound inside the package on a mandrel extending through a hole at the center of the package and being drawn from a supply through a slot in the periphery of the package; so that line may be withdrawn from the package either from the slot or from the hole after the package is filled.
In accordance with a more specific embodiment of the invention, plastic string trimmer line is wound into a sealed package in the form of a relatively flat cylinder with front and rear parallel walls separated by a circular band or edge which forms the space between the front and rear walls. An opening is provided through the rear wall on the central axis of the circular band; and a slot is formed through the circular band, between the front and rear walls. A mandrel having a winding surface on it is inserted through the opening in the rear wall into the space between the two walls. The leading end of a supply of plastic string trimmer line is inserted through the slot to engage the mandrel. The mandrel then is rotated to wind the line about the winding surface of the mandrel, within the package, drawing line through the slot as the winding commences. After winding has been completed, the mandrel is removed from the opening, leaving the leading end of the string trimmer line accessible through the opening in the rear wall. The opposite end of the string trimmer line is accessible through the slot in the circular band.